Improvement in sewing-machines



2 SheetsSheet I.

T. J. W. ROBERTSON.

Sewing Machine.

Patented Jun"12,1855.

2 Sheets-Sheet 2.-

T. J. W. ROBERTSON.

Sewing Machine.

Patented June12, 1855.

T. J. w. ROBERTSON,

on NEW YORK, N. 'Y.

IMPROVEMENT IN SEWlNG- MACHINES.

Specification forming part of Letters Patent No; 13,064, dated June 12,1855.

To all whom it may concern:

Be it known that I, T. J. W. ROBERTSON, of the city, county, and Stateof New York, have invented a new and useful Improvement inSewing-Machines; and I do hereby declare retained at. the back of thecloth.

Similar letters of reference indicate corresponding parts in the severalfigures.

This invention has reference to the employment of the needle thread orthreads alone for the performance of the stitch, and making what istermed in other machines the singlethread or chain stitch; and theimprovement consists in effecting such single or needle thread stitch bymeans of a detached and loosely-held looper and a reciprocating needlearranged and operating together essentially as hereinafter described.

A is the table upon which the cloth or other material is placed to besewed.

a is a needle with an eye near the point, attached to a slide, B, andreceiving the usual reciprocating motion by which it is caused to carrythe thread through the cloth to form a loop on the under side.

I) is the looper, which consists of a piece of metal which is straightexcept at one end, where it is slightly curved and pointed. This isplaced parallel with the needle, below the table A, with its pointdownward and its other end touching the under side of the table, and

- in such a position relatively to the needle that the latter will passclose or nearly close to its point. The looper is held stationary by aspring, 0, within a cavity in the face of a small block of metal, 0,which is secured to the stand of the machine; but it may be held in acavity made in the stand itself.

The needle passes through the cloth far enough to bring its eye belowthe point of the looper, and in so doing carries that part of the threadwhich is to form the loop very near the point of the looper. Immediatelyafter the needle begins to rise and leave the thread slack it alsobegins to turn on its center or axis toward the point. of the looper,and by that means throws the slack of the thread over the said point,and as it continues to rise it draws the thread in the form of a loopover the looper, which, without detaining the loop, merely keeps it openand in a proper position for the needle to passthrough it in its nextdescent. As tension is produced on the thread by the descent of theneedle, the loop is drawn entirely over and 01f the looper; hence it isapparent that the looper passes entirely through the loop. The turningof the needle on its axis to pass the thread over the point of thelooper is produced in the following manner: The needle-holder d isfitted to turn freely in a socket, e, attached to the slide B, withashoulder above and below to prevent it moving longitudinally withoutthe slide, and on one side it carries apin, f, which, during the descentof the needle, passes under aspring, g, which is secured to the guide Dof the needle -slide, and is by that means caused to work close to thesaid guide; but as the needle rises this pin, by reason of the bottom ofthe spring lying close to the guide,

passes up the inclined or curved lower part, h, of the spring, and isthus thrown forward and caused to turn the needle. Before thetermination of the ascent of the needle, the pin passes under and withina stationary inclined or curvedpiece, L, and by it is thrown back againinto contact with the guide D, and thus caused to turn back the needle.The spring 9 and piece 6 are shown in blue outline in Fig. 2, in whichfigure they are the most clearly shown.

What I claim as new and useful herein, and desire to secure by LettersPatent, is

Making a needle-thread, single, or chain stitch by means of a detachedand looselyheld looper, b, and reciprocating needle, ar ranged andoperating together in such a man ner'that, while the needle in itsback-stroke draws the slack of its thread onto or along and around thelooper, the looper, without de taining the loop formed by the drawing ofthe specified, is drawn entirely over and off the slack of theneedle-thread on and along it, looper b to complete the stitch,substantially guides and keeps the loop open, and the neeas described.dle and its thread in their next advance stroke pass through the open100p which, Witnesses: kept moving and having the further feed ofWVILLIAM TUscH, its own or needle thread passed through it, as R.BOEKLEN.

T. J. W. ROBERTSON.

